How to grow Kale

How to grow Kale

Only in recent years have the numerous health benefits of kale been rediscovered by British gardeners – and it’s about time too. Kale is one of the most accommodating crops you can grow, providing fresh greens in the depths of winter.

Just when the last of your summer crop has been cleared away, kale comes into its own, providing a steady supply of tender leaves right through winter to the following spring, and there are lots of different kings - from curly kale to black kale and others between. How to grow black kale (or cavolo nero kale) and growing curly kale use the same methods - it’s so simple!

Perhaps it was kale’s reputation as a tough and bitter plant that saw it lose favour, but harvested correctly when the leaves are still young, it makes a delicious addition to winter recipes and is bursting with healthy iron. It is extremely hardy and will thrive in almost any condition, surviving temperatures as low as -15°C and gracefully putting up with exposed and part-shaded positions that few other brassicas would. And frost only helps to improve its flavour, by turning the leaves’ starches to sugars.

As for the most part, kale has a high resistance to diseases, they will need less care than many other brassicas. Just remove any yellowing leaves that appear at the plants’ base.

Kale can be grown in a number of ways, either as a cut-and-come-again salad crop, harvested at the baby leaf stage, or as a mature source of tender winter greens. There are quite a few types available to give you the longest possible season of enjoyment: curlyleaved kales such as ‘Pentland Brig’ that have crinkled foliage similar to parsley; plain-leaved types like ‘Cottager’s’ with a more open shape; and rape kales for sowing in mid-summer for a spring crop.

Few crops will tolerate the range of soil conditions that kale does. It will grow in almost any soil so long as it is relatively free draining and has a good supply of nutrients. Can you grow kale in containers indoors, you might ask? You can try some varieties in containers, but non-dwarfing types will be quite large, so are usually unsuitable for this.

Preparing a growing position will pay dividends in the quantity of leaves – you can expect to harvest up to 1kg from a well cared-for plant. Pick a sunny spot if possible, although a part-shaded one will still leave you with a satisfactory harvest.

Growing kale from seed

Kale is usually started off in modules, pots or a seedbed before transplanting into its final home. The growing position should have been dug over the previous winter and a generous amount of well-rotted manure or homemade compost incorporated into the soil. If your soil is on the acidic side you will also need to add lime before planting to lower the pH until it is mildly alkaline (around 6.5).

Alternatively, you can follow kale on from an early summer crop such as peas or early potatoes, thereby maximising the use of available space. All that will be left to do once the previous crop has been removed is apply a dressing of organic fertiliser, such as pelleted chicken manure, a week or two before planting time as the soil will already have been well manured for the previous crops.

The kale growing season starts in April to early May if you are growing kale in the uk. The seeds can be started off in outdoor seedbeds by sowing into drills 1cm deep. Space the seeds thinly along the rows and leave 15cm between each row. Cover the seeds over and keep the bed moist to aid germination, which should take about 10 days.

Seedlings will appear in a wide variety of temperatures, so early success shouldn’t be difficult. Once they are up, remove excess seedlings to leave one young plant every 7cm.

When space is limited, sow seeds into modular trays or 7cm pots. Sow a few seeds per module, thinning to leave the strongest seedling intact. Use multipurpose compost for sowing and keep seedlings in a bright and relatively cool position to stop them becoming drawn and leggy.
Rape kales hate being disturbed and must be sown directly into their final growing positions.
Keep seedlings moist and allow them to grow on steadily. Do not allow them to dry out, which will unnecessarily stress the young plants and lead to poorer specimens. After about six weeks, in June or July, the plants will be ready to transplant into their growing positions. At this stage they will have around four to six leaves and be about 15cm tall, give or take 5cm.

Tamp down the soil of their new home with the back of a rake and lightly incorporate organic fertiliser if you didn’t do so a few weeks earlier. Do not dig the soil – kale likes a firm root zone and fluffing up the soil at this stage will only allow the plants to rock back and forth in the wind.

Carefully lift the young plants, taking care to preserve as much of the original root system as possible, and plant them with 45cm between plants in both directions. Module-sown seedlings will be easier to plant without disturbing the roots – just leave the growing media packed around them when transferring the young plant.

Set the plants a little deeper than they were previously so that the bottom leaves are just sitting on top of the soil surface and then firm them in thoroughly with your boot. Puddle the plants in by soaking them with water, which will further settle the soil around the roots.